Hard disk drives and other electronic equipment are often sealed within enclosures to provide a clean environment that is necessary for optimal operation of the equipment. For example, hard disk drives normally contain at least one inflexible platter or disk coated with magnetic material that is positioned within an enclosure. The disk is rapidly spun, and a magnetic read/write head “flies” a few nanometers above it in order to access or store data. The magnetic head rides on an air cushion, and it is desirable to position the head as close as possible to the disk without touching it in order to provide a high capacity drive.
Contaminants, including particles, gases, and liquids within the hard disk drive enclosure can act to reduce the efficiency and longevity of the hard drive. These contaminants can gradually damage the drive, cause deterioration in performance, and in certain situations even cause sudden, complete failure of the drive. Contaminants often enter the electronic enclosure from an external source, especially when the disk drive is subject to extreme environments, such as those used within portable music players. Common sources of contaminants in disk drives include leaks, which may or may not be intentional.
One particular concern regarding electronic enclosures is that contaminants from outside of the electronic enclosure should be prevented from entering the enclosure. These contaminants can be of particular significance because temperature fluctuations in the enclosure will often cause the exchange of air with the exterior environment. In recent years attention has been drawn to the possibility of sealing disk drive electronic enclosures so as to prevent the flow of gases into and out of the enclosure and further inclusion of an inert gas (such as helium) within the enclosure. However, filling an electronic enclosure with an inert gas can be difficult without inadvertently adding contaminating gases or without leakage of the inert gas out of the enclosure. Therefore, a need exists for improved methods and materials for controlling the flow of gases into and out of an electronic enclosure.